Abstract
It has been proved through numerical simulations and theoretical studies on a sky fook damper that the negative stiffness damper consisting of damping and negative stiffness elements has several advantages over traditional damping devices. One of the fundamental features of the device is to elongate the natural period of the structure by means of the negative stiffness that reduce or eliminate the “positive” stiffness of the structure, and absolute acceleration as well as absolute displacement of the structure are reduced accordingly. In order to realize a negative stiffness, however, the active controlled actuator or semi-active devices with sophisticated controllers and sensors are required at present.
In this research, a new device realizing a negative stiffness and damping in a passive manner was developed. The device consists of friction bearings having convex slope in order to generate the negative stiffness. The shaking table test was then performed using a girder model with rubber bearing supports in order to confirm the effectiveness of the device. Through series of experiments, it was observed that the structure's total stiffness due to the rubber supports could be declined by means of the negative stiffness.
